Volume of a Tube Converted to Gallons

Date: 08/01/97 at 18:15:13
From: Anonymous
Subject: Volume of a tube converted to gallons 

I have a length of round pipe that is 4" in diameter and 10 feet long.
How many gallons of water will it hold if filled and sealed at both
ends?

  Thanks Doc!

  Bob

Date: 08/02/97 at 23:26:07
From: Doctor Scott
Subject: Re: Volume of a tube converted to gallons 

Hi Bob!

First we need to find the volume of the tube.  From geometry, its 
volume is (pi)(r^2)h, where r is the radius and h is the height.  
We need, of course, to make sure that all of our dimensions are 
expressed in the same units. It will probably be easiest to change 
everything to inches.

Then, once you know the volume of the tube in cubic inches, we can 
change it to cubic feet, by dividing by 12^3. (Since 12 inches = 
1 foot, 12^3 inches = 1 cubic foot).

Finally, 1 cubic foot is approximately 7.5 gallons

Good luck!

-Doctor Scott,  The Math Forum
 Check out our web site!  http://mathforum.org/dr.math/